Centered tridecagonal number | C # Program to find nth centered tridecagonal number ; Function to find nth centered tridecagonal number ; Formula to calculate nth centered tridecagonal number ; Driver Code
using System ; class GFG { static long centeredTridecagonalNum ( long n ) { return ( 13 * n * ( n - 1 ) + 2 ) / 2 ; } public static void Main ( ) { long n = 3 ; Console . WriteLine ( centeredTridecagonalNum ( n ) ) ; n = 10 ; Console . WriteLine ( centeredTridecagonalNum ( n ) ) ; } }